Salesforce DictionarySalesforce DictionaryReusable business logic vs event-driven record handler
Apex Classes is a Setup page that lists all Apex classes in the org, including their namespace, API version, status, and size. Administrators and developers use this page to view, create, edit, compile, and manage Apex classes, as well as to schedule Apex jobs and check code coverage.
Apex Triggers is a Setup page that lists all Apex triggers in the org along with their associated objects, API version, and status (Active or Inactive). Triggers are pieces of Apex code that execute before or after data manipulation events like insert, update, delete, and undelete on Salesforce records.
| Dimension | Apex Classes | Apex Triggers |
|---|---|---|
| Invocation | Called explicitly from triggers, flows, APIs, or other classes | Fires automatically on record DML events |
| Structure | Standard class with methods and properties | Special syntax with trigger context variables |
| Reusability | Highly reusable across the org | Tied to a specific object |
| Testing | Can be unit tested directly | Tested by performing DML in test methods |
| Best Practice | Keep business logic here (handler pattern) | Keep thin — delegate logic to handler classes |
For reusable business logic, utility methods, web services, and batch processing.
For responding to record insert, update, delete, or undelete events on a specific object.
Other side-by-side breakdowns you might find useful